Twin BiSbO4 nanoseeds with {0 1 0}-exposed facets: Facile synthesis and excellent photocatalytic degradation of DDT in highly and long-term contaminated soil

Abstract

Twin engineering is one of the most recent perspective photoactivity enhancing approaches with its ability to provide highly ordered atomic arrangements that accelerate both the transport of free charge carriers and the electron-hole separation, but is still limited to a few photocatalysts, however. In this research, we report the controllable template-free synthesis and UV-photocatalytic activity of twin BiSbO4 nanoseeds with {010}-exposed facets for dichlorodiphenyltrichloroethane (DDT) degradation extracted from highly and long-term contaminated soils for the first time. The results revealed that the formation of the desirable BiSbO4 was strongly affected by precursors and hydrothermal time. Astonishingly, at optimized synthesis conditions, the as-synthesized BiSbO4 nanobundles containing twin nanoseeds enclosed by exposed {010} facets with an average length of 60 nm and width of 20 nm were resulted purely. The greatly enhanced photodegradation efficiency of the optimized sample with 98.5 ± 0.83 % removal of total DDT after 4 h of UV irradiation was achieved, significantly higher than that of the bulk sample (62.5 ± 0.77 %). The existence of both the exposed high-energy {010} facets and the coherent twin boundaries was suggested to contribute to the boosting of the DDT photocatalytic activity of the twin BiSbO4 nanoseeds with {010}-exposed facets. Additionally, a twin-dependent photocatalytic mechanism was also proposed for the twin BiSbO4.